Solve for $x$ and $y$ using elimination. ${4x+4y = 48}$ ${x+5y = 48}$
Explanation: We can eliminate $x$ by adding the equations together when the $x$ coefficients have opposite signs. Multiply the bottom equation by $-4$ ${4x+4y = 48}$ $-4x-20y = -192$ Add the top and bottom equations together. $-16y = -144$ $\dfrac{-16y}{{-16}} = \dfrac{-144}{{-16}}$ ${y = 9}$ Now that you know ${y = 9}$ , plug it back into $\thinspace {4x+4y = 48}\thinspace$ to find $x$ ${4x + 4}{(9)}{= 48}$ $4x+36 = 48$ $4x+36{-36} = 48{-36}$ $4x = 12$ $\dfrac{4x}{{4}} = \dfrac{12}{{4}}$ ${x = 3}$ You can also plug ${y = 9}$ into $\thinspace {x+5y = 48}\thinspace$ and get the same answer for $x$ : ${x + 5}{(9)}{= 48}$ ${x = 3}$